1. Field
Embodiments of the present embodiment relate to a washing machine with a ball balancer to reduce vibration generated during the dehydrating cycle and a method of controlling vibration thereof.
2. Description of the Related Art
In general, a washing machine (such as a fully automatic washing machine) includes an outer tub (hereinafter, referred to as a “tub”) accommodating fresh water such as washing water or rinsing water, a washing and dehydrating tub (hereinafter, referred to as a “rotating tub”) rotatably installed in the tub to accommodate laundry therein, a pulsator rotatably installed in the rotating tub to generate a water current, and a motor generating a driving force to rotate the rotating tub and the pulsator. The washing machine is an apparatus removing pollution from laundry with the help of the water current and surface activities of a detergent.
A washing machine performs washing of laundry through a series of operations such as a washing process of separating pollution from laundry with water in which detergent is dissolved (for example, a wash water), a rinsing process of rinsing bubbles and/or residual detergent within the laundry with water without the detergent (for example, a rinse water), and a dehydrating process of removing moisture contained in the laundry by rotating the laundry at high speed.
If the rotating tub is rotated in an unbalanced state where laundry is not distributed in the rotating tub when the washing is performed through the series of process, an eccentric force is applied to a rotating shaft of the rotating tub so that the rotating tub rotates eccentrically and then vibrations are generated from the tub. The vibrations are worse when the rotating tub rotates for the dehydrating process and bring out stronger vibrations and louder noise.
Thus, a washing machine having a ball balance is suggested to offset the unbalanced weight caused by the unbalanced laundry and to stabilize the rotation of the rotating tub. The ball balancer prevents an eccentric force from being applied to a rotating shaft by which balls move during the rotation of the rotating tub.
However, if gathering of the balls and the unbalanced laundry have the same phase (a same position) in the washing machine having a ball balancer, vibrations of the tub are worse in a resonant region (at early dehydration) when the washing process enters the dehydrating process so that the tub strikes a frame. Then, the overall washing machine vibrates abnormally so that a malfunctioned dehydration where the dehydrating process cannot be performed occurs. To solve this problem, water is supplied again to untangle the laundry and to perform the dehydrating process again. Thus, the quantity of water increases and dehydrating time is elongated.